The invention is in the field of ultrasonic devices for the treatment of hair and other fibers.
Devices that utilize ultrasonic mechanical vibrations are well known in the art. The treatment of natural and synthetic fibers to produce, alter, or remove a set has been the subject of prior work. For example, chemical agents are sometimes used, with or without heat, to produce a set in a fiber or for the removal of an existing fiber set. However, these methods are slow, laborious, ineffective, not topically efficacious, and the chemical agents used can ultimately damage the fibers being treated.
Ultrasonic mechanical vibrations are generally produced by Piezoelectric devices. Piezoelectric devices, which convert electrical impulses into mechanical vibrations, are generally based on the fact that certain crystals, when deformed by pressure, yield a mechanical motion. Resonant crystals and ceramics are used to generate such mechanical waves in solids and liquids. For high frequency, ultra-sonic vibrations to be generated, crystals operate in their thickness mode (the crystal becomes alternatingly thicker and thinner as it vibrates.)
Imai, U.S. Pat. No. 6,196,236, discloses a hair curling applicator that utilizes the longitudinal modes of vibration. Imai requires a user to manually wind hair around a hollow barrel. The hollow barrel oscillates longitudinally causing the wrapped hair to absorb ultrasonic energy in a shear (transverse) mode. Wrapping hair around the barrel is not convenient, especially if the hair has an applied treatment on it. Additionally, the user must wrap different portions of the treatment area sequentially, resulting in an inefficient use of time. Finally, safety is a concern, as the end of the vibrating barrel is not prevented from touching tissue. Such contact can cause sonic, deep tissue burns.
Shiginori, Japanese Publication JP 9-262120, teaches a hair drying, bleaching, and weaving device that also requires winding hair around a vibrating body. The presence of protruding vibrating bodies allows for an increase in treatment area, however, this teaching also requires wrapping hair around the vibrating body. Additionally, the protruding vibrating bodies do not provide uniform vibration as the protrusions at the end farthest from the generator deflect more than those closer to the generator. This limits the number of protrusions in order to maintain uniform motion. Finally, safety is problematic as the end of the vibrating body is not protected thus, the user could experience ultrasonic tissue burning.
Shigihara, U.S. Pat. No. 5,875,789 discloses a device for the permanent curling of hair. The user winds hair along a rod portion, where presumably longitudinal vibrations impart energy to the hair through frictional forces causing curling to occur. Again, wrapping hair around a rod portion is not convenient, especially if the hair has an applied treatment on it. Additionally, the user must wrap different portions sequentially, resulting in an inefficient time usage. Again, safety is a concern, as the end of the barrel is not prevented from touching tissue.
Goble, U.S. Pat. No. 3,211,159 discloses a hair treatment device that uses radial modes of vibration. This teaching does not require the wrapping of hair in order to provide treatment, however, multiple treatments are required in order to treat a large volume of hair. Additionally, safety is a large concern as a transducer that uses radial vibration modes can contact tissue and cause damage along the entire length of the transducer, and not just from the end as would happen from a transducer using longitudinal modes of vibration.
Therefore, it would be an improvement in the art to be able to provide a novel device that provides a treatment for a fiber, particularly hair, using a less reactive chemical agent, yet still provide a faster, less labor intensive, and more topically efficacious treatment experience.
In a non-limiting exemplary embodiment of the present invention, the fiber treatment device comprises an ultrasound generator capable of converting electrical energy to a mechanical vibration having a topically efficacious frequency, and a comb device responsive to the topically efficacious frequency coupled to the ultrasound generator. A reflector with a reflectance, R, is disposed on the distal end of the comb device and has a reflectance, R, expressed as |R| greater than 0.
In yet another alternative embodiment of the present invention, the fiber treatment device comprises an ultrasound generator capable of converting electrical energy to a mechanical vibration having a topically efficacious frequency, and a comb device responsive to the topically efficacious vibrations acoustically coupled to the ultrasound generator. A plurality of protuberances, each of which has a natural bending frequency, and has a proximal end and a distal end, extend outwardly from the comb device.